Ekko Balance
I think ekko is an alright champion I really like him in fact, barring 1 thing.
His stun.
Typically melee assassins have a few general problems, sticking to their target, dying before damage gets off, and most notably and almost universally, MELEE ASSASSINS DON'T GET HARD CC. Now I know that it would really hurt Ekko to remove the stun, in fact he would probably never be played. Also if you read his ability description it says:
"Ekko splits the timeline, creating an anomaly after a few seconds that slows enemies caught inside.** If Ekko enters** the anomaly, he gains shielding and triggers a detonation, stunning enemies by suspending them in time."
The if Ekko enters part is what's important here. I think that changing Ekkos basically guaranteed stun on anyone without flash/blink, to only working IF HE CROSSES THE BARRIER of his W would make him a lot easier to play against. This would be a significant nurf and would be able to keep his damage and sticking abilities and while at the same time keep him from being an overpower pub stomper. As is it would be probably be extremely hard to cross the barrier so his W would need a duration boost as well.
TLDR: Ekko's stun is to strong as is and should be changed to only stunning if Ekko can cross the barrier of his W